This type alows you to model information which takes one of predefined
values. There is not really an enumerated type (like `BOOLEAN` could
be); instead, you can define your own one, such as:

`DaysOfTheWeek ::= ENUMERATED {`

`sunday(0), monday(1), tuesday(2), wednesday(3), thursday(4), friday(5),
saturday(6)`

`}`

`Priority ::= ENUMERATED {low(-1), medium(0), high(1)}`

Although the notation is simmilar to notation of integers
with distinguished values, there are some important differencies, besides
the use of keyword `ENUMERATED`:

- the type defined is restricted to those values, that are named
- there is no numerical significance to the numbers involved; they are merely there to provide distinct representation for the various values
- there is no ordering relation defined
- only the identifiers, not the numbers, are used in the value notation

Thus it is purely correct to ommit those numbers in definitions. On the other hand, numbers are included, because of compatibility.